This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
| n | a(n) |
|---|---|
| 0 | 1 |
| 1 | 1 |
| 2 | 1 |
| 3 | 1 |
| 4 | 1 |
| 5 | 1 |
| 6 | 1 |
| 7 | 1 |
| 8 | 9 |
| 9 | 73 |
| 10 | 361 |
| 11 | 1321 |
| 12 | 3961 |
| 13 | 10297 |
| 14 | 24025 |
| 15 | 77221 |
| 16 | 926641 |
| 17 | 10696401 |
| 18 | 84365425 |
| 19 | 499445857 |
| 20 | 2395445521 |
| 21 | 9778915441 |
| 22 | 36584246161 |
| 23 | 248210675593 |
| 24 | 3971313933049 |
| 25 | 54773770095001 |
| 26 | 549282704399001 |
| 27 | 4258482133019401 |
| 28 | 27025791550397641 |